def DTL(examples, attributes, parent_examples, orig_examples, att_dict,
classes):
"""Holds the main algorithm componentes for creatin a Decision tree.
Recursive function with base cases for:
- no more examples available
- all remaining examples have the same class
- no more attributes available
Recursive step calls get_next_attribute() to decide which node to add next
"""
#orig_examples is used to be able to loop all v_values, even if some of the possible
#v_values are no longer present in examples at a given level of the tree
if len(examples) == 0:
return plurality_value(parent_examples)
elif check_if_all_same(examples):
return get_class(examples[0])
elif all(x is None for x in attributes):
return plurality_value(examples)
else:
next_attribute = get_next_attribute(attributes, examples, classes)
node = TreeNode(next_attribute, att_dict, classes, list(), list())
v_values = set(
column(orig_examples,
attributes.index(next_attribute) + 1))
next_attribute_index = attributes.index(next_attribute)
attributes[attributes.index(next_attribute)] = None
for i in v_values:
child_examples = [
x for x in examples if x[next_attribute_index + 1] == i
]
node.add_examples(column(child_examples, 0), int(i))
subtree = DTL(child_examples, attributes, examples, orig_examples,
att_dict, classes)
node.add_child(subtree, int(i))
return node
def _build_tree(self, lis, temp_id=1, parent=None):
if len(lis) == 0:
return None
if len(lis) == 0:
return None
parentnode = parent
if temp_id == 1 and parent == None:
val = lis[0]
parentnode = TreeNode(val, self.get_pos(val),
self.get_position(val), temp_id, parent)
temp_id += 1
for i in range(1, len(lis)):
if type(lis[i]) == str:
parentnode.add_child(lis[i], self.get_pos(lis[i]),
self.get_position(lis[i]), temp_id,
parentnode)
temp_id += 1
else:
subtreenode = parentnode.add_child(
lis[i][0], self.get_pos(lis[i][0]),
self.get_position(lis[i][0]), temp_id, parentnode)
temp_id += 1
useless, temp_id = self._build_tree(lis[i], temp_id,
subtreenode)
return parentnode, temp_id
for item in file_data2:
fileCount = fileCount + 1
nodes2.append(item)
print "number of reddits in the new dictionary %d " % fileCount
nodecount = 0
for node in nodes2:
if node.subscribers < 1000:
nodecount = nodecount+1
if node.subscribers is None:
print "There is a subreddit with no subscribers"
print "total nodes with less than 1000 subscribers % d " % nodecount
count = 0
reddit500 = []
for node in nodes2:
reddit500.append(node)
count = count + 1
print count
for node in reddit500:
if node.parent is None:
reddit.add_child(node)
# dump the data into a json file to create viz#
json_output = open('REDDITS4.json', 'wb')
a = "var viz_data = " + json.dumps(reddit.return_json()) + ";"
json_output.write(a)
json_output.close()